Principles to Help Guide Next Generation Interventions: Some Examples from Randomized Controlled...
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Transcript of Principles to Help Guide Next Generation Interventions: Some Examples from Randomized Controlled...
Principles to Help Guide NextGeneration Interventions:
Some Examples from Randomized Controlled Trials Concerning School Readiness
Craig T. Rameyand
Sharon L. Ramey
Presentation at conference on “Intervening Early: Progress and Opportunities
in Child Service Settings”Sponsored by NIDA, ACF, NICHD, NIMH, OBSSR & SAMHSA
Washington, DCSeptember 18-29, 2007
Scientific Foundation for Early Intervention
• Research on neuroplasticity (animal models)• Studies of extreme deprivation (orphanages, maternal deprivation, isolation)• Demonstration projects • Naturalistic and longitudinal studies• Randomized controlled trials (RCTs) to test the efficacy of a planned intervention to alter the life course
PRINCIPLES OF EFFECTIVE EARLY INTERVENTION
1. Timing (onset, duration, offset)
2. Intensity (per day/wk/mth/yr(s))
3. Direct learning experiences
4. Breadth of services/supports
5. Individual differences
6. Environmental maintenanceRamey & Ramey (1998), American Psychologist
Randomized Controlled Trials (RCTs)
we have conducted include:• Basic Studies of Early Learning
• The Abecedarian Project (ABC)
• Project CARE
• Infant Health and Development Program (8 sites)
• Romanian Orphanage Studies
• Intensive Pediatric CI Therapy (cerebral palsy)
• National Head Start-Public School Transition
Demonstration Study (31 sites)
• Pre-K Curriculum Comparison Study
• Child Care Coaching Studies
Ramey & Ramey
Applied Biosocial Contextual Development (ABCD):A Framework for Understanding Human Development
Examples illustrating these principles from some of our longitudinal RCTs
• Interventions for children from highly impoverished, often chaotic environments (Abecedarian Project and Project CARE; Romanian Orphanage studies)
• Targeted interventions for– Low birthweight, premature infants (IHDP)– Children with moderate to severe neuromotor
impairments (Project ACQUIRE)
Principle of Timing
• When the intervention begins and ends can significantly influence the impact on development
• Magnitude of this effect depends, in part, on the outcome measured, its developmental course, and the nature of the intervention
• Principle is highly similar to that in teratology
Campbell & Ramey, American Educational Research Journal, 1995
Two-Phase Design of Abecedarian Project
Control Group _• Adequate nutrition• Supportive social services• Low-cost or free primary
health care
Abecedarian Preschool Program
Treatment Group _• Adequate nutrition• Supportive social services• Free primary health care• Preschool treatment:
Intensive (full day, 5 days/week,50 weeks/year, 5 years)
“Learningames” CurriculumCognitive / Fine MotorSocial / SelfMotorLanguageIndividualized pace
Campbell & Ramey, 1995American Educational Research Journal
Brief Summary of Abecedarian K-2 Transition Program
• Individualized focus on academic and learning activities in school and at home
• Emphasis on reading, mathematics, and writing• Master Home/School Resource Teachers (12 children and
families per teacher)• Development of an individualized and documented
supplemental curriculum for each child• Explicit attention and action relevant to family circumstances,
as needed• Summer camps with academically relevant experiences
Ramey & Ramey, 1999
Campbell, Ramey, Pugello, Sparling, & Miller-Johnson (2001) Applied Developmental Science
The Abecedarian (ABC) ProjectLongitudinal Effect Sizes for Reading by Treatment Group
Key Findings from Abecedarian Project(“Abecedarian” …one who learns
the basics such as the alphabet)
18 Months to 21 Years Old• Intelligence (IQ)• Reading and math skills• Academic locus-of-control• Social Competence• Years in school,
including college• Full-time employment
• Grade Repetition• Special Education
placement• Teen Pregnancies• Smoking and drug
use
Plus benefits to mothers of these children (education, employment)
Ramey et al, 2000
Principle of Dosage
• Interventions which are more intensive (as indexed by hours per day, days per week, etc.) produce larger changes
• Exact specification of “optimal doses” has been very difficult, largely due to cost and pragmatic issues
• Some evidence consistent with “threshold hypothesis” (mostly at lower limit)
• Highly similar to dose-response curve principle in teratology
• Support comes mainly from cross-study comparisons
Principle of Direct Learning Experiences
• Interventions that directly alter the child’s experiences (i.e., transactions with others and environment) have significantly greater effects than do those that indirectly change the child’s life (e.g., parenting programs, coordination of service delivery supports)
• Note: majority of early interventions have focused on indirect effects based on idea that these would lead to sustainable environmental supports (to date, this hypothesis has not been confirmed)
Project CARE
* RCT designed to replicate Abecedarian Project (ABC)
* Added a new treatment group to test the efficacy of
an intensive 5-year home visiting program using the
ABC intervention (to test indirect vs direct effects)
* Affirmed same findings in early childhood through
to young adulthood from educational intervention, but
no benefits of home visiting on child outcomes
Adapted from Wasik, Ramey, Bryant, & Sparling. Child Development, 1990
Principle of Breadth of Services/Supports
• Early interventions that are multi-component and address child needs in health, cognition, social-emotional development generally produce larger and longer lasting effects
Limitations: – Research evidence has many confounds, since broader
programs also tend to be more intensive and include direct learning experiences
– most intervention programs tested in RCTs focused on children with multiple needs and risk conditions (due to natural co-occurrence)
• Some children benefit more (or less) than do other children
• This principle has been affirmed primarily by:– Findings that children with greater needs for
environmental supports benefit more– Findings that children with more substantial CNS
insult may not benefit as much from generic (i.e., not spectrum-specific intervention) intervention
• Similar to teratology principle of differential genetic susceptibility or Gene X Environment Interaction Effect
Principle of Individual Differences
The Infant Health and Development Program (IHDP)
• Intervention replicated Abecedarian Project• New target group = premature, low birthweight children
gestation and < 2500 gm at birth• Conducted at 8 sites (N=985 children & families)• Intervention modified for specific biological risk factors• Educational intervention lasted only until 3 yrs old (CA)•Follow-up reported through age 18 yrs IHDP, JAMA, 1990
Examples of findings affirmingPrinciple of Individual Differences
• In ABC, children with lowest IQ mothers (<70) showed markedly larger benefits than those whose mothers had IQs >90
• In IHDP, intervention more efficacious in preventing mental retardation (IQ<70) for premature, low birthweight children with less educated mothers or lower IQ mothers
• In IHDP, very low birthweight infants did not benefit as much
Stanford-Binet IQ Scores at 36 MonthsHeavier LBW Group (2001-2500gm)Infant Health and Development, JAMA, 1990 Ramey, AAAS, 1996
Infant Health and Development, JAMA, 1990 Ramey, AAAS, 1996
Stanford-Binet IQ Scores at 36 MonthsLighter LBW Group (<2000gm)
Children’s IQ at 36 months: Maternal Education X Treatment Group
70
75
80
85
90
95
100
105
110
Some HighSchool
High SchoolGraduate
Some College CollegeGraduate
Control
Intervention
(n=232)(n=162) (n=166)(n=104) (n=134)(n=63) (n=76)(n=48)
Infant Health and Development Program
Ramey & Ramey (1998), Preventive Medicine
Principle of Environmental Maintenance
• Benefits of early intervention are sustained longer when children continue to receive strong, appropriate environmental supports after intervention ends
Limitation: Almost impossible to separate effects of subsequent depriving or harmful environments (which could reverse benefits of early intervention) from the need for true “maintenance”
Some Implications of Principles for Service Settings
1. Develop flexible alternative compounds of services for benefit/cost studies rather than evaluate single service comparisons
2. Expect and plan to discover subgroups of participants who exhibit differential levels of risk and who may show differential levels of response to treatment
3. Develop an explicit model for population and subpopulation characteristics; intended primary pathways through which services are intended to have an impact on specific outcomes which are themselves monitored in an ongoing fashion
Some Implications of Principles for Service Settings
4. Develop adequate data systems to document frequency and quality of service availability and service utilization at the individual level
5. Conduct analyses and report them publicly at least on a yearly basis
6. Do not assume that appropriate control group participants are, or should be, an untreated group
7. When possible, establish explicit partnerships with relevant agencies